Yes, you could put on 20" rims, but why? It will slow down your car greatly. As far as lowering springs, I'm not sure what the tolerances would be with the 20's + lowering, but I think you'll find that if you go with 20's, you won't need to drop it.
ya know personally i wouldnt go any bigger than 18". With 20 and lowered will cause some rubbing issues im sure. those are def nice rims, but i would go with 18's. eventually im gonna buy the chrome bullit rims!
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'97 with built 3.8 from Supersix
Tma turbo kit
448hp @15psi 11.09@124mph
XXXhp @21psi 10.71@125mph
Fastest Single Port V6 Mustang w a Ported Stock Upper Intake
20" wheels will destroy any good traits the car has.
They'll suck all the torque out of your engine, the car will be "tippy" and will not handle well, plus all the rotating mass bouncing around will shake the car and the occupants to pieces.
20" wheels belong on heavy cars that can contain the rotating mass, and even then there are tradeoffs. on a lightweight car, forget about it.
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Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
i would def. stick with 18's .. it will fill in the wheel space and not kill your performance that much. 20's are way to heavy on mustang to use with performance, but for all show it wouldnt matter and the 99 and up mustangs are bit too heavy for the lightwieght 20 inch racing rims (specially the sn197 models). I mean you could still throw them on it would just bend and warp em way before they should be in that shape
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2004 4.6 mustang GT - completely stock ATM.
Up for sale !!!!! will deal and talk trades .. PM ME
Dang I like the 20s but since its bad I will just go with the 18s.
And does anybody know what springs I should get?
What's your budget?
THat's going to determine whether you want to go with sport srpings from Steeda, Roush, or Ford Racing or go to a coilover setup.
If you go coilover, there's some chassis prep work you should do first.
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Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
Need to shore up the strut/shock towers. they weren't designed to hold both the spring and the damper.
Kenny Brown's Strut tower brace, for example puts a plate on top of the tower to reinforce it.
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Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
Yeah, those aren't coilovers, so you can go with whatever brace you want.
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Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
I'd go with Steeda, Ford Racing, or Kenny Brown Sport Springs,
Those will loosen your fillings, especially with big wheels.
That brace is for Cobras.
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Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
20 inch rims with lowering springs? 
